Up: Linux Software Encyclopedia
Last checked or modified: Feb. 4, 1999
- X Organization
- X.Org is the worldwide consortium responsible for the collaborative
development of the
X Window System.
- X Animation is an animation package with a panel
interface for convenient access to animation, display,
and colormap functions. Typical workstation performance
numbers are a display rate of 50 frames/sec or better with
400x400 8-bit images.
The source code for xa is available. It is written in C
and can be installed on generic UNIX workstations with
the XView widget set.
Binary versions are also available for DEC Alpha, Linux Intel,
SGI IRIX, and Sun SunOS and Solaris platforms.
- A protocol for implementing home automation
by controlling appliances and the like via hardware
plugged into wall sockets. Communication is via the standard
electrical wiring in a house.
- A program to operate the CM11A computer interface that runs the
- A program that allows X10 commands to run programs
or perform other tasks on a UNIX box.
This can be used to, for example, playing a welcome message when a
motion sensor detects that you've entered a room.
- X11 (X Window System)
- A software package created at MIT to provide a uniform environment
for graphical programming on UNIX systems.
It is publicly available, has been implemented on many systems
(including the XFree86 port for Linux
systems), and defines a programming style based on a client/server
model with an explicit separation of hardware-dependent components
and application programs.
The X Window System consists of four major components:
X Organization as well as
Cutler et al. (1992),
Ferguson and Brennan (1993),
Heller et al. (1994),
Johnson and Reichard (1994),
Mui and Pearce (1992),
Mui and Quercia (1994),
Nye and O'Reilly (1992),
Quercia and O'Reilly (1993a),
Quercia and O'Reilly (1993b),
Sheifler et al. (1988), and
- an X Server program running on the application user's computer
which controls the graphical display hardware and handles input and output;
- X Clients, i.e. application programs that use the display and
input resources of computer that may not be the one on which they're
- the X Protocol which consists of the types and uses of messages that
control interactions between X Client applications and the X Server; and
- the X Library which provides an API for X Protocol exchanges
Each new version of the distribution contains new functionality.
The new functionality in R6 included:
The new functionality in R6.1 included:
- the X Image Extension (XIE);
- the Inter-Client Exchange Protocol and Library;
- the X Session Management Protocol and Library;
- the Input Method Protocol;
- X Logical Font Descriptions;
- the SYNC, XTEST, BIG-REQUESTS and XC-MISC extensions; and
- the PEX 5.1 protocol and library.
The new functionality in R6.3 included:
- the X Keyboard extension;
- double buffering for smooth animation; and
- protocol recording.
The new functionality in R6.4 included:
- support for Web integration;
- protection of data from untrusted client connections;
- a bandwidth- and latency-optimized protocol for using X across
- a print protocol following the Xlib API; and
- support for vertical text writing and user-defined characters
in the Xlib implementation.
- Display Power Management Signaling (DPMS) for setting ``green'' computer
monitors into power saving mode;
- Extended Visual Information (EVI) to allow applications to discover
more about the graphics capabilities of the server than is possible with
the core protocol;
- Colormap Utilization Policy (TOG-CUP) to allow applications to discover
desktop special colors, e.g. Windoze reserved colors on PC-based X servers,
and store read-only (i.e. sharable) colors in specific locations in a
- Xinerama, a wide screen server that combines two or more screens into
a single virtual screen.
Quite of bit of documentation in PostScript format is freely available
with the X distribution. The documents in the X11R6.4 distribution
Entries related to the administration of or basic programming
with X11 include:
- Xaw/Xaw3d, a common widget set built on top
of Xt and Xlib;
- xdm, a display manager for managing one or
more X displays;
- x11perf, an X11 server performance test
- X-extension, a
Python interface to Xt,
Xaw and Motif;
- XFree86, a port of X11
to Intel x86 processor-based platforms;
- xfsft, patches to X11R6 that enable the
use of TrueType fonts;
- XIE, an X11 extension providing a mechanism
for transferring and displaying images;
- Xlib, the basic C
library interface to X11 on which many higher-level widget sets are
- XMX, a utility for sharing an X11 session
on multiple displays;
- Xt, an object-oriented interface implemented
on top of Xlib for creating graphical components.
- A program for seasonally adjusting economic time series as developed
by the U.S. Census Bureau.
The Fortran program includes an extensive
set of time series model building capabilities for fitting regARIMA
models, i.e. regression models with ARIMA errors.
Such models are used to extend series with forecasts (or backcasts)
to improve the seasonal adjustments of the most recent (or earliest)
A source code distribution is available as is a user's manual
in PostScript format.
- An abacus X widget.
- An XSL processor for transforming
XML documents into HTML,
text or other XML document types.
Version 1.0.1 is a complete and robust reference
Java implementation of
XSLT and XPath.
Xalan can be used from the command line, in an applet or servlet, or
as a module in another program.
It uses the Xerces XML parser but can
interface to any XML parser conforming to the
DOM level 2 or
SAX level 1 specification.
The features of Xalan include:
- implementation of XSLT version 1.0 and
XPath version 1.0;
- optional use of the Document Table Model (DTM) for avoiding
the object overhead of constructing and manipulating DOM trees;
- interfacing with a SAX document handler or any XML parser that
can produce Java DOM trees;
- output to either SAX or DOM;
- support for Java and scripting language
- a redirect extension to support the production of multiple output
documents in a single operation.
- A package consisting of high-level, multi-mission utilities
for X-ray astronomical spectral, timing, and imaging data
analysis. A general plotting program is also included.
The components of XANADU include:
- XSPEC, a spectral program for command-driven, interactive
designed to be detector-independent (and has been used with
data from HEAO-1 A2, EXOSAT, Ginga, ROSAT, BBXRT, ASCA, CGRO and IUE);
- XIMAGE, an imaging program for multi-mission X-ray
image display and analysis
designed to be instrument independent and to support the analysis of
data from any X-ray imaging detector provided that the proper
calibration files are available;
- XRONOS, a general purpose timing analysis package
consisting of a collection of programs for light curves, hardness
ratio and color-color plotting, epoch folding, power spectrum and
autocorrelation analysis, cross-correlation analysis, time
skewness, and general statistical analysis; and
- QDP/PLT, a plotting package wherein the Quick and Dandy Plotting
program reads ASCII files containing various plotting commands and
data and calls PLT subroutines which execute the commands and plot
the data (using the PGPLOT subroutine library).
The source code for the XANADU system is available as are binaries
for Sun SunOS and Solaris, SGI IRIX, and DEC Alpha and Ultrix
platforms. Compilation is straightforward via the use of a system
of make files which can be modified fairly easily for compilation
on other platforms, e.g. Linux. The code is written in Fortran
Each of the three main components XSPEC, XIMAGE and XRONOS are
available in a separate distribution as is the
QDP/PLT package (which is bundled with various other libraries
used by the system).
The system is well documented with separate manuals available for
each component in HTML and PostScript formats.
- A Java application for
building data-driven, cross-platform Web applications
that integrate disparate data sources.
The Xang architecture cleanly separates data, logic and
presentation, and is based on open standards.
It extends the behavior of existing Web servers by allowing
authors to create applications that respond to
requests and generate dynamic output synthesized
from different data sources.
A Xang application is defined by a single .XAP file
that aggregates multiple data
sources, makes that data URL addressable and defines
custom methods to access that
data. These custom methods can be invoked through
simple HTTP requests, via a Web
browser or simple client side API.
Data sources are aggregated into one unified hierarchy
via XML includes and Java
plug-ins which implement the standard DOM APIs. These
plug-ins provide two-way
access to the data via the DOM API.
A .XAP file is an XML text file that defines the data
sources, the mapping of requests to
methods, and the logic of the methods. The structure
of the .XAP file is a hierarchy of
URL addressable elements.
- A program for viewing a wide variety of animation formats
under X11. Currently supported are FLI, FLC, IFF, GIF87a,
GIF89a, DL, Amiga PFX and Moviesetter, URT RLE, AVI,
MPEG and WAV format. This should install
and run on generic UNIX boxes
- A GTK-based GUI for
- A Tcl/Tk front-end to the
- The Athena Widget Set is a library package layered on top of
Xt and Xlib that
provides a set of user interface tools which can be used to
build a variety of applications. It extends the basic
abstractions provided by X and provides a higher layer of
functionality by supplying a cohesive set of sample widgets.
The original Xaw has been updated with a 3-D look in a version
called Xaw3d, which has itself
been improved in a package
All are available at the given URL.
It is included in the standard
X Window System distributions.
See also Xraw and
- A set of 3-D widgets based on the X11R5 Athena widget set,
Xaw3d may be used as a general replacement for Xaw.
Almost any Xaw-based application can be relinked with Xaw3d to
obtain a 3-D appearance, and with shared libraries libXaw can
be replaced by libXaw3d to obtain a 3-D appearance without even
- An improved version of the X Athena Widget 3-D widget set (Xaw3d)
which adds such features as:
the capability of playing .au files,
true 3-D menus with borders having 3-D bevels rather than flat
right-hand scrollbars in the text widget,
a new scrollbar style that allows both arrows to be at one end of
the capability of placing borders around the actual text in some widgets,
better color handling of 8-bit displays,
- A small suite of Video4Linux-related
- xawtv, an X11 application for the
bttv driver for watching TV;
- fbtv, a TV applications for the Linux console that uses
the framebuffer devices in kernels 2.2.*;
- set-tv, a command-line tool for setting
- streamer, a command-line tool for capturing still images
and AVI videos with sound;
- webcam, which captures images and uploads them via
FTP to a Web server in a loop; and
- radio and kradio, console- and
KDE-based radio listening applications.
- An X.500 Directory User Agent (DUA) which allows the searching
and modifying of database entries.
It supports both X.500 and Kerberos
authentication and has a context-sensitive hypertext help
It is highly configurable with the search options, display
configuration, and help system all modifiable.
A source code distribution of xax500 is available.
Compilation requires the Motif library
as well as the UM-LDAP package.
- The X11 Bellcore Application
Environment consists of a set of widget classes for displaying
captions and for displaying collections of objects in matrix format.
XbaeMatrix is a Motif widget which
presents an editable array of string data in a scrollable table
similar to a spreadsheet. It has callbacks for doing field
validation and customizing traversal, and allows cells
to be assigned independent colors. It allows rows, columns,
and regions of cells to be selected or highlighted, and the
matrix can be dynamically grown or shrunk by adding or deleting
rows and columns at any position. There are many resources
available with which the matrix can be customized, and pixmaps
can be displayed in individual cells.
XbaeCaption is a simple Motif manager widget used to
associated a caption (XmLabel) with its single child.
The label can be either an XmString or a pixmap and can
be displayed in any one of twelve positions around the perimeter
of the child.
A source code distribution of Xbae is available.
The widgets are written in C and can be compiled and used
on many UNIX platforms via the use of the Imake
script included in the distribution.
Each widget is documented in a man page.
- A DBMS in the form of a class and function library for manipulating
Xbase type datafiles and indices.
This supports both C and C++ programs.
The available routines includes those for supporting multi-user access
for .DBF databases, fields, Dbase II and IV memo fields, dates,
record and file locking, and NDX indices.
A source code distribution is available.
This is documented in a user's guide in HTML format.
- An emulator for the Acorn BBC
Model B computer which runs on UNIX/X Window systems.
- The XML Bookmark eXchange Language is an interchange
format for the hierarchical bookmark data used by currently available
It is an application of XML.
- The eXtended Basic Linear Algebra
Subroutines are a set of Fortran 77
programs which perform various matrix and vector operations
not in the the regular BLAS.
The programs in this package include:
- CDCDOT, which computes complex precision dot products and adds
a scalar via the use of double precision accumulation;
- CSROT, which applies a Givens plane rotation to a complex matrix;
- DCDOT, which computes a complex precision dot product using
double precision accumulation;
- ISAMIN, which finds the smallest index of the minimum magnitude
component of a real vector;
- ISMAX, which finds the smallest index of the maximum component
of a real vector;
- ISMIN, which finds the smallest index of the minimum component
of a real vector; and
- SCOPYM, which copies the negative of an array into another
array with corresponding increments.
A source code distribution of XBLAS is available.
All routines are written in Fortran 77 and documented via
comment statements contained within each source code file.
This is part of CMLIB.
- An X Window chess program that you can play against. It
whups me regularly but I'm no Bobby Fischer. The source
code is of the form xboard*.tar.gz.
- A Lisp dialect used at the University
Its salient features include automatic code optimization and
the capability of adding additional activities to Lisp
functions, instructions, and variables which don't affect
Xbvl also has interfaces to X11,
Xaw, and OpenGL
(including the Mesa library).
A source code distribution of Xbvl is available. The
basic compiler is written in portable C.
All of the documentation contained within the distribution
is written in, as you might expect, French.
- A full X-based CD writer program which is the successor to
the cdwtools program.
It is a front-end from some other CD-related programs like
(both of which are included in the
These programs make it possible to
copy or create CDs with just a few mouse clicks.
The features include:
A list of supported CD writers can be found at the home site.
- automatic SCSI hardware setup;
- copying of ISO-9660, non-ISO-9660, mixed mode, and audio CDs;
- mastering of ISO-9660 data CDs;
- creation of audio CDs;
- quick CD to CD copying; and
- a automatic logfile facility.
The X-CD-Roast package is written in C and Tcl/Tk
and also requires the Tcl Tix extension.
A compiled binary of Tcl/Tk/Tix is included in the distribution.
Installation is easy with the included makefile.
The package is documented in an HTML-format user's guide
included with the distribution.
The January 1998 issue of the
Linux Journal contains an introduction
- An IRC client for X11 that
uses GTK. The features include:
A source code distribution is available.
- the look and feel of AmIRC for the Amiga;
- DCC SEND, RECEIVE and RESUME;
- mIRC color;
- multiple server/channel windows with one thread;
- dialog windows; and
- optional Perl scripting.
- A package for drawing high-quality electrical circuit schematic diagrams
and similar figures. The XCircuit graphics capabilities are object-based
and can be used for drawing arbitrary figures similar to
It is especially useful for drawing tasks requring the repeated use of
standard graphical objects, e.g. architectural drawing, printed
circuit board layout, or music typography.
The features of XCircuit include:
- creating new objects such as polygons, boxes, arcs, splines,
texts, arbitrary user-created objects, and paths that join elements;
- various text creation and editing capabilities including changing
fonts and font styles, changing justification, overlining and underlining,
subscripts and superscripts, editing existing test, and using special
characters in text;
- element editing tasks including deleting and undeleting, copying
selecting and deselecting, rotating, flipping horizontally and
vertically, aligning to grids, changing border styles, transferring
elements between pages, changing object size and color, etc.;
- editing arcs, polygons and curves;
- creating and editing libraries of elements;
- main window options such as zooming in and out, panning, creating
and changing grids, changing color schemes, adding fonts and colors, etc.;
- loading files in XCircuit and LGF formats; and
- exporting files in XCircuit, LGF and PostScript formats.
Source code and binary distributions of XCircuit are available, with
the latter including an executable for Linux Intel platforms.
The source can be compiled on most UNIX/X11 platforms via the
In addition to the basic program there are is also a repository
of object libraries including both the basic and contributed sets.
Documentation includes an online tutorial.
- An Xlib-based GUI toolkit written in
C++ that has the look and feel of Win95.
It is mostly independent of the underlying window manager, although
some special features require support in
The classes currently (3//97) implemented included simple
widgets (i.e. labels and icons), push buttons with either
text or pixmaps, check and radio buttons, menu bars and
pop-up menus, scroll bars, a scrollable canvas, list boxes,
combo boxes, group frames, text entry widgets, tab widgets,
general purpose composite widgets for building toolbars and status bars,
dialog classes, and top-level window classes.
This is available either as source code or as a binary for
Linux Intel systems.
- A C++ layout library for the X Window system
in which all objects (called gadgets) are font sensitive, i.e. their
size changes automatically with the size of the screen and window.
All gadgets have the same base class and are put together in
groups which manage the correct size of all gadgets inside.
Xclasses can be used to easily construct font and context sensitive
Xclasses is available in binary format for
Linux Intel, SGI IRIX and IBM AIX platforms.
The distribution also includes several example programs built with
The library is documented in a large user's guide in PDF format
which is thus far (4/97) only available in German.
- A mail user agent (MUA)
for UNIX systems which was designed
mainly to read and write mail with attached data, e.g.
mail with MIME types.
XCmail is POP3
capable and was built using the
Xclasses layout library.
It also has encoders that can encode/decode binary data into
ASCII to allow transporting via Internet mail.
Other features include a GUI interface designed to be largely
support for multiple mailboxes,
an address book for favorite email addresses,
and support for PGP within PGP MIME format
A source code distribution of XCmail is available.
- An interactive 2-D overlapping grid generator.
Overlapping grids consist of a number of component grids wherein
boundary-fitted curvilinear components resolve the details
near the boundary of the computational domain and the background
grids, often Cartesian, covering the remaining parts of the domain.
Xcog works via a set of commands for creating and manipulating
the grids or meshes.
These commands include:
and several more.
- make-mapping, for designing a new mapping;
- change-mapping, for changing the properties of an existing
- copy-mapping, for creating a new mapping and copying all
values from an existing mapping;
- transform-mapping, for rotating, translating and scaling a
- color-mapping, for changing the color of a mapping;
- mark-mapping-boundary, for identifying external segments of
mappings that are aligned with the boundary of the computational domain;
- make-curve, for designing a new curve;
- boundary-condition, for changing the boundary conditions of
- grid-lines, for setting the number of grid lines for mapping;
- overlap-parameters, for changing the overlap parameters;
- compute-overlap, for setting the parameters for the composite
grid and computing the intergrid communication from a selected subset
of component grids;
A source code distribution of Xcog is available. It is written
using Fortran, C and Xlib and should
be usable on any UNIX platform with all three capabilities.
It also requires the HDF library for storing
the calculated grids.
It is documented in a user's guide available in PostScript and
- An emulator for the 3Com or USRobotics Pilot or
PalmPilot or Palm III that runs on UNIX/X11 systems.
Source code and binary distributions are available.
- A multiwindow mouse-based text editor for the
X Window System.
Xcoral is a direct Xlib client and
runs on color or black and white X displays.
The features of Xcoral include:
- a built-in browser which enables navigation through C functions,
Java classes, methods and files;
- a built-in small ANSI C interpreter (Smac) which
dynamically extends the editor's functionality to user-defined
functions, key bindings, modes, etc.);
- the provision of variable width fonts, menus, a toolbars, scrollbars,
buttons, searching, region selection, kill-buffers, macros and
- an online manual box with a table of contents and an index;
- facilities to aid in the creation of LaTeX
and HTML documents;
- commands accessible from either menus or key bindings;
- color syntax highlighting for C/C++/Java modes with auto-indent and
a RCS interface; and
- accessibility of UNIX commands from within the editor.
Xcoral is available for Sun SunOS and Solaris, Linux Intel,
IBM AIX, HP-UX, SGI IRIX, and DEC Alpha OSF/1 platforms.
The documentation is available online from within the
- A UNIX utility that dumps files in hexadecimal, decimal or octal with
ISO characters optionally side by side. File addresses can also be
shown in any of these formats.
It can read files in any of the formats it writes and create binary
files from the data therein.
Thus you can dump a binary file with xd, edit it with a text editor, and
then recreate the binary file with the changes.
It can also transform a binary file into a C data declaration which
permits embedding its contents into a program.
A source code distribution is available which is documented in a man page.
- A data visualization or viewing package that does vector
plots, contour plots and color maps. It slices and dices 3-D
data and will plot in Cartesian or cylindrical coordinates.
The author says that it is portable to any UNIX platform
with the X Window system.
- A color imaging and data analysis tool based on the
X Window system. It was developed for the analysis of 3-D 32-bit
floating point scientific data stored in NCSA
format. Features include color raster
display of 2D slices from 3D datasets, display of actual data
values in spreadsheet form, continuous and single-step animation
of color raster images, tiling of multiple images in a single
window, arbitrary slicing and dicing, 3-D visible volume
rendering, and many more. The source code is available as well
as binaries for Cray, Dec (3100 and Alpha), IBM, SGI, and
- An XML DataBase Manager is a database
for XML files.
The use of XML offers several advantages including greater
speed (since the data has already been parsed)xi and less memory
usage (since only the required parts of the XML file are loaded
This is available under the QPL.
- A binary delta generator library developed with the intent of replacing
RCS in PRCS.
XDelta is a library interface and application program designed to
compute changes between files. It can apply these deltas to a copy
of the original file(s) and also includes a simple implementation
of the rsync algorithm as well as several
advanced features for implementing RCS-like
The improvements in XDelta over RCS include:
A source code distribution is available which requires
zlib and GLIB for
compilation and use.
- easily discarding old versions in date order regardless
- retrieving all versions in time proportional to their age and not
- using a new file format that allows individual deltas to be compressed
as they age so the entire archive need not be compressed at once;
- freeing higher applications such as PRCS from the hidden performance
implications of version number allocation; and
- the efficient synchronization of archives, even when their contents
are disjoint and differently ordered.
- The X11 Display Manager is a program for managing
one or more X displays either on a local host or remote servers.
It is basically the graphical analog of such programs as
init, getty and login on character terminals.
Running this will produce a graphical login screen (via the
Xdm keeps a list of servers to manage and also listens to the
XDMCP (X Display Manager Control Protocol) port for other servers
It spawns a copy of itself for each managed server and runs a script
to set up the user environment when a user has been authenticated
via entering a password.
A configuration file called xdm-config allows the
configuration of many aspects of xdm. This is usually located in
/etc/X11/xdm or /usr/X11R6/lib/X11/xdm.
The xdm program runs other scripts in this directory. The order
is Xsetup (then the login), Xstartup (as root),
Xsession (as the user), and Xreset (at the end of
the session to clean up and reset the server).
The Xsession script can also be used to run .xinitrc
to start various X resources such as window managers.
If xdm is not used, then the X server is usually started with
the startx command.
This program is included in the standard X11 distributions and
described in a man page.
- The eXternal Data Representation standard is for the
description and encoding of data for the purposes of transferring data
between different computer architectures.
XDR uses a data description language which allows the concise
representation of intricate data formats.
It is not a programming language and can thus only be used to describe
data, allowing intricate data formats to be described in a concise manner.
XDR fits into the ISO presentation layer and
is somewhat analagous in purpose to
X.409, the ISO Abstract Syntax
Various other protocols such as
NFS use XDR to describe the format of their
Related software packages include:
- A program for displaying TeX DVI files under
- A version of xdvi modified to work with
the kpathsea path searching library.
Other additional features include:
- a file selection dialog box;
- support for HyperTeX; and
- support for Omega.
- A package for developing slides for online presentations using
LaTeX and xdvi on a Linux PC running
- A program that sets the X11 root window to an image of the Earth
as seen from a chosen vantage point and correctly shaded for the
current position of the Sun.
This will work on almost any UNIX/X11 platform.
- An interactive text editor for the
X Window System based on the Athena
Similar to aXe.
- A program that runs one or more X11 server performance tests and
reports how fast they are executed by the server.
It is meant to comprehensively exercise every X11 operation that
can be performed.
This measures window management performance as well as traditional
graphics performance, including benchmarks for the time it takes
to create and map windows, to map a pre-existing set of windows
onto the screen, and to rearrange windows.
It also measures graphics performance for operations frequently
used by X applications.
This can be used to analyze the strengths and weaknesses of
particular servers, as well as for server intercomparisons.
This is included in standard X11 distributions and is described
in a man page.
- This is an alternative to GNU
Emacs originally based on an
early alpha version of version 19. This used to be known as
Lucid Emacs through version 19.10. Almost all features of GNU
Emacs are supported or implemented in a better way in XEmacs.
Features include more bundled packages than GNU Emacs, binaries
for many common operating systems, a built-in toolbar, better
Motif compliance, variable-width fonts, marginal annotations,
ToolTalk support, horizontal and vertical scrollbars, better
APIs for attaching fonts, colors, and other properties to text,
the ability to embed arbitrary graphics in a buffer, and
complete compatibility (at the C level) with the Xt-based
- A package to create ASCII menu environments or GUIs on UNIX
systems. Xenmenu uses an easy menu programming language
which enables menus to be quickly created and modified on
the fly. It can also be used as a shell, the purpose for
which it was originally created.
A source code version of Xenmenu is available.
It is currently (1/98) in the Alpha testing phase.
- A simple X Window-based
text editor for such tasks as editing
source code, system configuration files, scripts, or other
ASCII text files.
The features include:
- speed, simplicity, and low memory use;
- search by substring or regular expression;
- unlimited undo and redo;
- display of line numbers;
- some X resource configuration although mostly command keys;
- some error dialogs; and
- multiple files in separate windows.
A source code distribution of Xenon is available.
It is written in C++ and can be compiled on most
UNIX platforms using g++.
It is documented in a man page.
- An interactive astronomical ephemeris package with a number of interesting
capabilities. It provides many graphical views as well as quantitative
heliocentric, geocentric, and topocentric information for
Earth satellites, the solar system, and celestial objects.
This highly interactive program is controlled via a main menu
that provides control and display of three basic services:
observing circumstances, looping, and access to additional displays.
Observing circumstances include location, time, and (for the
refraction model) atmospheric conditions.
Looping is the ability to set things up to automatically increment
time at a selected step size and rate.
Additional displays provide all of the graphical and quantitative
information that is available.
A large database is included in the distribution as well as
the capability of reading other popular astronomical databases.
Extensive context-sensitive help is available on all screens.
The main Xephem menu provides access to various views including:
All views can be dumped to a PostScript file for external viewing
- a sky view that displays the sky in RA-Dec or Alt-Az mode at any
scale, automatically loads Hubble GSC and/or PPM/SAO field stars,
displays information about constellations (e.g. names, figures,
and boundaries), shows the Bayer designations in a Greek character
set, offers coordinate grid or a round or square eyepiece
overlays, allows scenes to be flipped either way, and has
a zoom capability;
- a moon view based on a high resolution, full gray-scale image
which can be displayed at four different magnifications, can
can display umbral and penumbral boundaries during eclipses,
an optional lunar latitude and longitude grid overlay,
a true sky background, a user adjustable Earth shine proportion,
and subsolar, subearth, and libration information that can be computed and
a database of over 1200 lunar features that can be labeled;
- an Earth view that can be switched between cylindrical and spherical
formats, has an easy trail setup for watching Earth satellites,
displays solar eclipse ground locations, object tracks as they
orbit, locations of hundreds of observatories and cities,
a grid overlay, and a sunlight underlay;
- a solar system view that displays planets, asteroids, and comets with
the capability of displaying all loaded asteroids and comets at once,
slider controls providing the capability of viewing from any vantage
point, an optional stereo view for comet trajectories, and a move demo mode;
- a Jupiter view that displays the moons and the Great Red Spot;
- a Saturn view that shows its moon sand rings, both with a true
sky background; and
- a Mars view that displays an image based on a 1-square-degree orbiter
A source code distribution of Xephem is available as are
binaries for HP-UX, SGI IRIX, DEC Alpha, Linux Intel (ELF),
and Sun SunOS and Solaris platforms.
Compilation requires the Motif library.
The package is documented in a man page and (mostly) via on-line
context sensitive help.
- A Python module for performing astronomical
computations. It is primarily intended to compute, for an arbitrary
data and location on the Earth, the position of the Sun, Moon, planets
or any asteroid or comet whose orbital elements are available.
Additional functions include utilities for computing the angular
separation between two objects, determining the constellation in which
an object lies, and finding the times at which any object rises, transmits,
and sets on a specific day.
This is based heavily on Xephem.
- An XML parser with advanced functionality
including XML Schema,
DOM Level 2 version 1.0, and
SAX Version 2.
The features include:
- optional document validation;
- optional inclusion of external general entities;
- optional inclusion of external parameter entities
and the external DTD subset;
- optional performance of namespace processing;
- duplicate attribution declaration warnings;
- lazy or full DOM node expansion;
- optional creation of EntityReference nodes in the
DOM tree; and
- optional creation of nodes describing the
grammar in the DOM tree.
- See Uts.
- The X Window Extended Simulator of 2-D
Cellular Automata is a general purpose simulator
for the 2-D cellular automata popularized in John Conway's
Game of Life. This extends the original game such that the
state of the cells at t+1 can depend not only on their state
at time t but also at time t-1.
A source code distribution is available that has been tested
- The X11 Eurobridge Widget set contains a set of
widgets for displaying and presenting basic types of information,
e.g. text, images, graphics, audio and video.
It currently (5/97) supports multinational mixed text,
raster images (PBM,
JPEG/JIF, TIFF, GIF), 8kHz uLaw sound,
and MPEG-1 video.
Each widget is a container for information which is imported
into the widget in one of these formats.
Sample programs which demonstrate the basics of the widgets
These are: viewer, which activates a Xew widget into an
Xaw Porthole widget and controls it with
a Panner widget;
simple, which activates widgets into separate shells;
texted, a raw low-level interface to the XeTextEd
widget which can be used to test its features; and
audio and video for testing those capabilities.
A source code distribution of Xew is available.
It can be compiled and used on several UNIX platforms
using the supplied autoconfig
It is documented in several ASCII and HTML files included
in the distribution.
Xew is used in the Wafe package.
- An extensive Python interface to
the X Window System libraries including
the X Toolkit (Xt), the Athena widgets
(Xaw), and the Motif widgets.
An interface to the NCSA Mosaic HTML
widgets is also included.
- A package which allows the interactive building and modification
of a graphical user interface (GUI) based on the
The output generated by XF is a script which can be executed
with wish or any other Tcl/Tk interpreter.
The source code for XF is available.
Installation and use requires Tk 4.x.
The program is documented in a 120+ page user's manual
available in PostScript format.
- A contouring program for iso-lines. It features high-quality
nonlinear interpolation with bicubics on a rectangular grid,
area filling, X Window and PostScript output, customization
with a resource file, interative labeling of contour lines,
interactive data probing for value and derivatives, placing
of symbols according to information read from a file, exact
location of extrema and saddle points, and computation of profiles.
It should install and run on UNIX boxes with an ANSI C compiler
and X Windows.
- An X Window fax program which includes
a fax viewer and several other tools which are used via
the graphical interface to send and process faxes.
It supports front page generation, ASCII,
conversion and more.
It is based on the efax program but can also possibly be
used with Hylafax.
The tools included in the distribution are:
- faxserver, which inspects the spool directory for faxes
and sends them all in sequential order;
- faxqueue, which moves the complete fax directory with all
G3 files, front page and faxinfo to the spool directory;
- faxdirect, an alternative fax program which will attempt
to send the fax immediately through a fax modem;
- g3toxpm, which produces (using efix) a
PPM file from a
G3 file and calls ppmtoxpm to convert it into
- giftog3, which converts a GIF file into a G3 file; and
- g3view, which views on G3 page.
Xfax is available either as source code or as a binary distribution.
Compiling from source requires the XForms
library and the efax distribution.
The use of the package additionaly requires that both
Netpbm software be installed on your system.
A Linux-specific makefile is included with the source distribution.
The program is documented is the README file in the distribution.
- A user-level library that works with the Linux kernel
framebuffer driver to provide hardware-accelerated 2-D drawing
The API provides direct access to graphics card framebuffer memory
and automatically uses the accelerated graphics chipset features
It also provides identical functionality in software for drawing
on dumb framebuffers and off-screen bitmaps.
This is a full-screen API intended as a base platform for a windowing
system or gaming/multimedia library.
- A toolbar for the X Window System which provides an easy way to
launch other applications.
The XForms Cool Enviroment is entirely configurable
via the mouse and uses the FVWM window manager
as a default.
A source code distributionof XFCE is available as are binaries for
several platforms including Linux Intel.
- The eXtended FDisk package is a replacement for DOS
FDISK. It additionally includes a boot manager that allows
more than one operating system to be installed.
The features include:
- support for multiple visible primary partitions;
- installation of the boot manager without changing the partition table;
- warnings for boot block modifications;
- command line parameters for controlling default partition types;
- optional Partition Magic compatibility;
- master and partition passwords;
- optional disabling of new partition initialization for recovery
- support for disks greater than 8 GB.
- A menu-driven X11 tool that allows the drawing and manipulating
of objects interactively in an X window. The resulting pictures
can be saved, printed or converted to a variety of other formats.
The use of xfig requires the
TransFig package, which contains the
post-processor needed to convert fig files to one of several
Xfig is used by selecting icons in the drawing and editing
panel windows and then moving and clicking the mouse appropriately
(or using keyboard equivalents). Several basic drawing objects
are available, including circles, ellipses, polylines, polygons,
boxes, arc-boxes, regular polygons, arcs, text, encapsulated
PostScript objects, splines, closed splines, interpolated splines,
and closed interpolated splines. In the editing mode one can
choose to glue together primitive objects to create compound
objects, break compound objects, scale objects, align objects,
move a point, move an object, add or delete points, copy/cut to
a buffer, delete, edit objects, update, flip vertically or
horizontally, rotate, turn a polygon into a closed interpolated
spline object, add and delete arrows, and more. More choices are
usually available under most editing functions, e.g. a choice of
fonts for text, etc.
The xfig package can be installed on most generic UNIX platforms
with X11. An Imake configuration file is supplied to ease
installation. The package is documented in a man page available in
both troff and PostScript formats, as well as in a quick overview
in PostScript format.
- A viewer for FITS data format images for
UNIX/X11 systems. XFITSview features include:
All defined FTIS image data types
are supported and normal or gzip compressed files may be used.
The package supports Digitized Sky Survey (DSS) coordinates as
well as the standard World Coordinate Systems (WCS).
- zooming and scrolling;
- modification of various quantities (e.g. brightness, contrast, and
- determination of celestial positions in an image;
- logging the positions and brightnesses of selected pixels;
- marking specified positions in an image;
- comparing images via blinking; and
- viewing 3-D images in the form of a movie.
The source code for XFITSview is available. It can be compiled
and installed on most UNIX/X11 platforms which have the
Binary versions are also available for HP-UX, IBM AIX,
SGI IRIX, DEC Alpha, Linux (a.out and ELF) Intel, and Sun
SunOS and Solaris platforms.
The program features extensive online documentation.
- An XForms-based mail application for
UNIX operating systems.
It is partially compatible with mh style mailboxes
but doesn't require any mh tools to be installed on the system.
The features of XFMail include:
- a graphical user interface (GUI);
- full configurability via the GUI;
- support for mail retrieval from either POP or a spool file;
- sending mail from either sendmail or an SMTP gateway;
- an internal address book;
- a flexible rules database;
- support for faces and picons;
- full MIME support;
- support for IMAP 4 remote folders;
- multiple address books with mailing list support;
- flexible message filtering rules;
- multiple signatures with attachment rules;
- multi-lingual and PGP support; and
- a configurable internal editor and online help.
The XFMail package is available in source code form.
It is written in C and requires the XForms
library and the XPM library for compilation.
It is documented via on-line help files.
- A library and program that allow you to build interaction forms
with buttons, sliders and many other widgets in a simple way.
The library consists of a large number of C routines that are used
to build forms with the available widgets. These routines can be
used in both C and C++ programs.
The design goals for XForms were to create a package that is
intuitive, easy to use, powerful, aesthetically pleasing, and
The basic idea behind XForms is that of a form, i.e. a window on
which different objects or widgets are placed.
A form can be defined with relatively few lines of code, and
several commonly used forms (e.g. choosing a file) have special
routines that allow them to be defined in a single line of code.
User interaction with the application forms created is fully
handled by the library routines, and that interaction can take
place in a number of different ways. The widget classes available
include buttons, sliders, input fields, menus, browsers, etc., and
adding new classes is a straightforward task detailed in the manual.
To make things even easier a Forms Designer is included with the
package. This program lets you interactively design forms and
generate the corresponding C code. Objects can be chosen and
placed and attributes changed using just a mouse.
The distribution includes the library, the GUI builder, and source code
for over 50 demonstration programs.
It is available only in
binary form for Linux, Sun, SGI, DEC Alpha, HP, IBM RS6000, FreeBSD,
NetBSD, BSDi, unixware, Solaris, SCO, DEC Ultrix, Cray and
Convex systems. A 200+ page tutorial and reference manual
in PostScript format is avaiable separately.
The Feb. 1996 issue of the Linux Journal
has an article about XForms by
A large number of applications have been built based on Xforms including:
and many more.
- DAP, a digital audio processor for UNIX;
- EMTOOL, a program for the display and
manipulation of electron micrographs;
- Lyx, a WYSIWYG front-end for
- MAD, an image processing system for recovering
images from blurred or noisy representations;
- Ra-vec, a raster to vector image converter;
- RPlay, a X11 control panel for the RPlay
network audio system;
- Unix Cockpit, a UNIX/X11 file manager;
- Xfax, an X11 FAX program;
- XFCE, an X11 toolbar;
- XFMail, a mail user agent;
- xldlas, a statistical applications package;
- XUser, an X11 interface to shadow password
- XWatch, a logfile viewer;
- A Perl extension which provides access to the
XForms GUI API library and thus allows
X applications to be written completely in Perl.
The Xforms4Perl distribution comes with a collection of
demonstration programs which range from simple API examples to
full-fledged system utilities and applications.
- The organization that ports the
X Window system to Linux platforms.
There is also an
XFree86 FTP site.
See Hsiao (1999).
- A set of patches to X11R6 that enable the use of
- An X11 font server for TrueType fonts.
- An environment for the design, verification and synthesis of
fuzzy logic based systems.
It is based on a high-level abstraction fuzzy specification language
called XFL and has a structure consisting of:
- a kernel formed by a set of common functions called the XFL library
that perform the passing and semantic analysis of XFL specifications and
store them using an abstract syntax tree;
- a set of modules in charge of the different design stages around
the kernel library; and
- the GUI on top of the modules.
The module programs in Xfuzzy include:
A source code distribution is available which can be compiled and used
on UNIX/X11 platforms with the Athena toolkit.
Extensive documentation is available online and in the distribution.
- xfplot, a module for plotting surfaces involving fuzzy system
variables using Gnuplot;
- xfsim, a verification module;
- xfbpa, a supervised learning module for tuning the parameters
of XFL definitions;
- xfc, a module for compiling inference engines into C code;
- xftl, a module for translating an XFL specification into a
look-up table that can be implemented on a FPGA;
- xfvhdl, a module for translating an XFL specification into a
VHDL description based on a specific architecture; and
- modules implementing membership and rule editors.
- An extension of the Motif widget set
which provides many of the controls found in MS Windows
The widgets in Xg include:
Also included are a set of utility functions XgUtils
for performing various tasks.
- XgClockLabel, a digital clock widget which uses standard
strftime() format strings;
- XgComboBox, an implementation of an MS Windows combination
- XgExtPushButton, which allows pixmaps
(XPM) and text to
be simultaneously displayed;
- XgFastLabel, a label widget designed to be much faster
than XmLabel and in which text can be rotated in any direction;
- XgNumEntry, a numerical entry widget which allows for range
limiting and input verification;
- XgTabs, a tab widget which can be oriented on any side of
- XgTimeEntry, a date/time entry widget; and
- XgToolBar, a toolbar widget which allows any widget on an interface
to be registered for drop onto the toolbar.
The Xg widgets can be used on any generic UNIX/X11 platform
There is at present (5/97) no available documentation.
- An X Window interface to Gnu Common Lisp
It provides windows,
menus, and graphics functions. It also provides an interactive
system for making drawings, drawing programs, and graphical
- The X Window Graphical
Kernel System is an X11
version of the ANSI GKS. This is a
full level 2C GKS system.
This has been installed on several UNIX/X Window platforms and
special instructions for installation on Linux platforms are
given in the indicated distribution.
The documentation consists of a set of man pages, a manual
describing the C language binding used by XGKS, and a manual
explaining the implementation-specific aspects of GKS that
are particular to XGKS.
- A dynamic graphics program for data analysis implemented on
the X Window System.
The dynamic graphical methods offer the capability of motion,
extensive interaction, and rapid response for discovering
and understanding higher-dimensional relationships among
XGobi features the manipulation of scatterplots which can
be single-variable strip plots, pairwise plots, or linear
combinations of three or more variables. They can also
be transformed in many ways, and plots can be moved and
reshaped and variables transformed interactively.
It is designed to be a complement to existing analytical tools.
An example is its capability to work simultaneously within
the S statistical language environment (see R).
The functionality of XGobi includes:
- one-variable textured dot plots;
- two-variable scatterplots to which connected lines can be added;
- 3-D rotation around an arbitrary axis with trackball control,
including the ability to save coefficients of rotation;
- grand tour rotation, i.e. a smooth randomized sequence of
2-D projections for exploring a higher-dimensional point cloud;
- a projection pursuit guided tour, i.e. a method for helping the
grand tour find interesting views of the data;
- brushing, i.e. the ability to change the color or plotting
character of a point or group of points including the ability
to transmit that information to other windows and save indicator
vectors of brushing information;
- moving and reshaping data in the plot region;
- identification, i.e. displaying the case label or row number of
an interesting point by positioning the cursor near it, including
the ability to cause the same point to be labeled in other windows;
- variable transformation; and
- on-line help.
A source code distribution of XGobi is available. It is written in
C and can be compiled on genertic UNIX/X11 platforms, e.g.
it compiled and installed on the first try on my Linux Intel box.
A 1992 version of the user's manual in PostScript format is
available in the same directory as the source code, although more
recent manuals are available for $. See the Readme.doc
file in the distribution for details on how to obtain newer manuals.
- An interactive plotting program for creating line plots
and restricted surface plots. It draws a graph on an X display
given data read from data files or standard input. It can display
up to 64 independent data sets using different colors or line
styles to distinguish them. It annotates eachgraph with a title,
axis labels, grid lines, tick marks, grid labels and a legend,
and has the capability to modify most of the these. This version
has been modified to perform simple animation tasks.
The source code of XGraph is available as well as binaries
for Cray, Convex, HP, IBM, SGI, Sun and Linux platforms.
- An easy-to-use and powerful package for drawing graphs.
I'd really like to describe this in a bit more detail but
the documentation is thus far (4/97) only available in French.
Xgraphic is available in binary form for Linxux Intel (ELF),
Sun Solaris and SunOS, DEC Alpha, IBM RS6000, SGI IRIX,
and HP700 platforms.
Their is a user's manual available in PostScript format which
is written in French.
- An emulator for the
Apple IIGS computer. This is available as source code
or in binary format for several platforms including
- A package for measuring the efficiency and visualizing the
Hough transformation and its variants for line detection.
The package has a graphical interface although the components
can also be used in a command-line mode.
The package include implementations of the standard,
randomized, dynamic randomized, window randomized,
random window randomized, curve fitting, probabilistic,
adaptive, combinatorial, and dynamic combinatorial Hough transforms.
XHoughtool can be used to examine binary edge pictures with
backgrounds signed by zeros and edges by values between 1 and 255
in several formats including PGM, CVL,
VIS, SKE and RAW.
A source code distribution of XHoughtool is available.
The transforms are written in C and the GUI using
Xlib and XView.
Documentation can be found in the distribution as well as
in Kälviäinen et al. (1996).
- XHTML (Standard)
- A family of current and future document types and modules that reproduce,
subset, and extent HTML 4 document types as
XML 1.0 applications.
XHTML family document types are XML based and are designed to
work with XML-based user agents.
XHTML 1.0 is a reformulation of the three HTML 4 document types as
applications of XML 1.0.
XHTML 1.0 is mostly intended as a bridge that allows the increased use
of XML while maintaining compatibility with browsers that support
The chief differences between XHTML 1.0 and HTML 4, with most having
to do with the former being stricter than the latter, include:
- tags are all lower case;
- elements must nest, i.e. no overlapping;
- all non-empty elements must be closed;
- empty elements must be terminated;
- attribute values must be quoted;
- attribute values cannot be minimized; and
- the addition of <script> and <style> elements.
- An HTML editor
that facilitates the creation, development
and maintenance of HTML files. It is written in C using
and the NCSA HTML Widget. This is also known as ASHE.
There is a binary version of
this available as well as the source code.
This is also called ASHE.
- An interactive C-like
with vector extensions
to make it more amenable for the quick analysis and manipulation
of data from numerical simulations or scientific experiments.
Calculations can be done interactively via an interpreter to
obtain instant feedback, or file containing Xi statements can
be processed via batch operation.
Xi is capable of a wide range of numerical and visualization
techniques and can produce pixel or vector output graphics.
It also supports the PVM
message passing system for performing calculations on a virtual
supercomputer comprised of several workstations in a cluster.
The visualization capabilities of Xi include the creation of
2-D (e.g. function, contour, and vector plots as well as images
and multiple plots) and 3-D (e.g. function, surface and velocity
plots) plots. Output can be generated in X11, PostScript and
PPM formats (the latter for use by the
Xi also has a vector-oriented X11 graphics utility that allows
the user to freely change the size and relative position of objects
within a single window. It presently uses specially developed
graphical widgets although versions using either the FSF widgets
or Motif are planned.
The numerical library of Xi contains a large number of algorithms
and functions including those for:
Most parameters don't have to be set when using the
Xi library since it infers them from the context. Planned
enhancements include a Xi to C++ translator to allow for compiled
programs and an object-oriented extension to Xi itself.
- linear algebra (e.g. solving
linear equations, inverting matrices, QR-, LU-, and SVD-decomposition,
determination of eigen-vectors and -values, calculation of
determinants and condition numbers, etc.);
- numerical integration and differentiation;
- interpolation and approximation (e.g. cubic
splines under tension, least squares fits, least orthogonal
distance fits, etc.);
- fast Fourier transforms and their inverses;
- multi-dimensional ODEs (e.g. nonstiff and stiff methods);
- special and complex functions; and
- random number generators.
Xi is available in binary form for DEC Alpha (OSF), Linux (a.out and
ELF), DEC Ultrix, IBM RS6000, and Sun SPARC Solaris platforms.
The documention is available as a tarred package of hypertext
documents or as a couple of separate PostScript documents.
- A utility that converts X11 XBM, OS/2 (v1.2 and v2.0), Windows,
and Mac icons into OS/2, Windows, and X11 XPM files.
A source code version (written in C) is available.
- The X Image Extension provides a mechanism
for the transfer and display of almost any image on hardware
which can support the
X Window System.
It provides a large and robust set of image rendition and
enhancement primitives which can be combined into arbitrarily
complex expressions as well as import and export facilities for
moving images between clients and servers.
While XIE doesn't try to be a general image processing system, it
does provide tools for image enhancement as filtering operations such
as contrast enhancement, convolution, dithering, geometric transformations,
and histogram generation.
It also provides support for the transmission of compressed images
between client and server to forestall bottlenecks which might be caused
by transmitting the large amounts of low-level data found in images.
The XIE package is included in standard X11 distributions.
See Logan (1988).
- A color imaging and data analysis tool based on the X Window
system. It features display of actual data values in spreadsheet
form, Cartesian and polar color raster display of data images,
black-and-white contour and shaded data plots, color palette
creation and manipulation capabilities, animation of multiple
color raster images, expansion of images for greater detail,
notebook capabilities, color contours, and more. The source code
is available along with binaries for several platforms, and it
should install on generic UNIX platforms running X Windows.
- A powerful and flexible framework for generating indexes for
many kinds of documents, e.g. those created using
Nroff, HTML, or even
It is not fixed to any specific system and can be configured for
a wide variety of purposes.
Xindy can be configured to process indexes for many languages with
many different letter sets and different sorting rules.
It also has user-definable location types and highly configurable
A source code distribution of xindy is available as are binaries
for several machines including Linux Intel.
It is documented in both a turorial and a user's manual, both
available in PostScript format.
- A free video player for UNIX-like systems.
The features include:
- playing MPG-2 and MPG-1 video;
- playing unlocked/unencrypted DVDs;
- playing video CDs and SVCDs;
- playing AVI files using Win32 codecs;
- synchronized audio and video; and
- optional full screen using the Xv extensions in
- A secure replacement for inetd whose features include:
A source code distribution is available.
- built-in access control;
- logging different services to different files;
- making services available only during specified times;
- preventing denial of service attacks by placing limits on servers;
- specifying ranges of IP numbers in the form 188.8.131.52/30;
- redirecting services to different hosts and ports; and
- binding different services to different interfaces.
- A personal finance tracking and performance tool.
Xinvest lets you:
- centralize record keeping by storing all transactions in account-specific
- calculate total and annualized returns including the effects of
buys, sells, and dividends;
- plot various transaction parameters such as share price, shares per
transaction, transaction cost, etc. in transaction-based bar or date
based X-Y charts;
- view asset allocation of accounts in a portfolio;
- use a financial calculator with common financial equations; and
- save the session state for the next session.
Xinvest is available either as source code or as a statically-linked
ELF binary for Linux boxes.
Compilation requires both the Motif
and XPM libraries.
- The X User Interface
Toolkit is an object-oriented user
interface development environment for the X Window system based
on Common Lisp,
CLOS, CLX and CLUE. It is a framework for
Common Lisp/CLOS applications with GUIs for the X Window
system, and contains user interface toolkits, including
general building blocks and mechanisms for building arbitrary
user interface elements and a set of predefined common elements
(widgets), as well as high-level interactive tools for
constructing, inspecting, and modifying user interfaces by means
of direct manipulation. The system is stable although still under
active development. A partly incomplete XIT manual in PostScript
is available, as is the source code. It is known to run on
the freely available Common Lisp implementation CLISP as well as
on Allegro CL, a commercial implementation.
- A fast, portable, multithreaded web server which is scalable
and efficient at high loads. It is based on the
SMT multithreading kernel and
faster than most free or commercial web servers.
Xitami supports the HTTP operations GET, POST, and HEADER as
well as virtual hosts, CGI, clickable image maps, CERN/NCSA logging,
log cycling, protected directories, direction execution of
Perl programs, and extensive configuration
It handles all connections within a single processes without
creating child processes (like most other servers), which makes
the cost of creating new connection very low.
It was built from the ground up as a high performance web server
engine which can serve large files quickly while handling many
simultaneous hits. It is also economical with disk space, memory,
and CPU time, and installs in minutes with many configuration
options including complete virtual hosting.
Additional Xitami features include:
- full HTTP/1.0 compliance;
- multihomed hosts based on IP addresses;
- direct support for CGI scripting languages;
- Java applet support;
- user-defineable MIME types;
- allowance for multiple document roots;
- use of the basic authentication protocol;
- customizable error messages;
- automatic HTTP port fall-back;
- on-the-fly server reconfiguration and user/password management; and
- a customizable CGI interface.
The source code for Xitami is available. It can be installed
and used on any system which can compile ANSI C and has
a standard socket library.
It is documented in a user's guide available in
- The X-based Image
processing Tools and Environment
is an image processing system that allows the processing,
transformation and description of images to be performed with
many built-in functions. New functions or programs can also
be created by the user within the system. Images are stored
and processed in an internal format called the Blab Image
File Format (BIFF) although some other popular formats can
be used. The main display program in XITE is xshow which
also serves as a graphical user interface to almost all the
The over 170 available programs in XITE include those for:
- format conversion (i.e. writing to TIFF,
binary, ascii, MATLAB and Sunraster and reading from all but PostScript);
- statistics (e.g. size, min, max, median, etc.);
- image representation (e.g. subimages, merging images, pyramid, etc.);
- arithmetic operations (e.g. negate, scale, absolute value,
complex conjugate, multiply, etc.);
- logical and relational operations;
- rotation, mirroring and affine transformations;
- convolution and filter design (e.g. lowpass, highpass, bandpass and
- Fourier, Hartley, Haar and Hough transforms;
- color manipulation (e.g. gamma correction, dithering,
- histograms and scattergrams;
- global and local thresholding;
- binary thinning and canny edge detection;
- the generation and addition of noise;
- various morphological operations;
- non-supervised classification; and
- texture estimation.
The XCITE source code is available and runs on Sun SPARC,
SGI Indy and Power Challenge, DEC Ultrix and Alpha, IBM RS6000
and Linux systems. The documentation consists of a user's
manual and a programmer's manual with both being available
in hypertext and PostScript formats.
- An object-based framework for implementing network protocols
which defines an interface that protocols use to invoke operations
on one another, i.e. to send a message to and receive a message
from an adjacent protocol. This is also a collection of libraries
for manipulating messages, participant addresses, events, associative
memory tables, threads, etc. The distribution also includes
x-sim which allows the x-kernel to be run as a network simulator
as well as on top of a real network.
The distribution includes the source code which is written in C.
It has been tested on Linux (Intel), SGI IRIX, DEC OSF/1, and
Sun SunOS and Solaris systems. Much documentation in the form
of various manuals and technical reports are available in HTML
and PostScript format.
- A recorder/replayer for the X Window System.
The features of Xlab include:
A source code distribution is available that has been successfully
installed on several platforms including Linux Intel.
- written using Xlib for maximum portability;
- it sits between clients and server and is transparent to both;
- it is non-intrusive and can automate any X11 application;
- the recorded files are in human readable and editable ASCII format; and
- it can be used as an X protocol analyzer.
- X Lies, Damned Lies And
Statistics is a program for interactively performing
various statistical tasks.
It can perform most standard statistical tasks such as
data summaries, OLS regression, ANOVA, line plots, scatter
plots, and histograms. It also includes some experimental
data fitting techniques which use neural networks and
Xldlas is available either as source code or in binary
format for Linux Intel, HP-UX, and OS/2 platforms.
Compiling the source requires the
Documentation is a bit sparse but this software practically
teaches how it use itself.
- The eXtensible Log Format is an
XML-based format intended to make log information samrter and easier to use.
- A utility which allows several types of images to be viewed
under X11 or loaded onto the X11 root
window. Several options are available for the modification
of images prior to viewing, including clipping, dithering,
depth reduction, zoom, brightening or darkening, input
gamma correction, and image merging. A utility
(xlito) is provided which allows these options to be appended
to the image files.
It currently (version 1.16) supports several formats including
CMU Window Manager raster files, Faces Project images,
Fuzzy Bitmap (fbm) images, GEM bit images, GIF images,
G3 FAX images, JFIF-style JPEG images,
McIDAS areafiles, MacPaint images, Windows or OS/2 MPB Images,
monochrome PC Paintbrush (pcx) images, photograph on CD images,
portable bitmap (pbm, pgm, ppm) images, Sun monochrome and
color RGB rasterfiles, Targa (tga) files, URT
(rle) files, X pixmap (xpm) files, X10 and X11 bitmap files,
and X Window dump files.
The source code for xli, written in C, is included in the
distribution and can be compiled on most generic UNIX/X11
platforms, with compilation eased by the inclusion of an
The package is documented via a man page.
See also xv,
- A C subroutine library that application programs
or clients use to interface with the X Windows system by means
of a stream connection.
It is the C language interface to the X protocol and represents
the lowest and most tedious level of X programming, i.e. all events
such as button presses or window exposures must be explicitly managed
on this level.
A 480+ page reference
guide that provides a detailed description of each function
and related background information is available in PostScript
format in the standard X11 distribution, although it is not
a tutorial or user's guide. See the
- display functions
to return information about the display;
- window functions to
create, destroy, configure and change windows;
- window information functions;
- pixmap and cursor functions;
- color management functions;
- graphics context and graphics functions;
- window and session manager functions;
- event handling functions;
- input device functions;
- internationalized text functions;
- inter-client communication functions;
- resource manager functions; and
- application utility functions.
- An evolutionary improvement over the earlier XPLUS with many
enhancements and bug fixes.
A source code distribution is available which can be compiled
on several platforms including Linux.
- An extensible statistical computing environment for
data analysis, statistical instruction and research with
an emphasis on providing a framework for exploring the
use of dynamic graphical methods.
Extensibility was achieved by building it on top of
the Xlisp language, a Lisp dialect that is most closely
related to Common Lisp
although it also contains some
extensions to support object oriented programming.
The window system interface was designed to work identically
in different GUI environments (e.g. Mac OS, X Windows and
The prototype object-oriented programming system is
used to implement the graphics system as well as to
implement statistical model representations such as
linear and nonlinear regression and generalized linear
models. The statistical modeling features were
enhanced by adding extensions to standard Lisp arithmetic
operations to perform element-wise operations on lists
and vectors and also by adding a variety of basic statistical
and linear algebra functions. The statistical functions include
functions to return the density and quantiles for a number of
types of distributions, to compute means and medians, to
perform max/min tasks, to compute lists of random numbers, and
many more. Plotting functions include those to create boxplots,
histograms, x-y plots, scatter plots, probability and contour
plots, and to rotate plots in 3-D space.
Implementations of Xlisp-Stat are available for Macintosh,
Ms Windows and UNIX/X11 systems, with the first two available
in binary and the latter in source form. I had no problems
compiling and installing it on my Linux platform.
documentation includes a somewhat dated book, a more up-to-date
tutorial introduction and several technical reports. All but
the book are available in both HTML and PostScript format.
The Xlisp language implementation is included in the
Xlisp-Stat package but is also available separately.
Several ancillary programs written
by third-party users are available at the
UCLA Xlisp-Stat Repository.
There is also some third-party documentation available.
The Surfer's Guide to Lisp-Stat
is a good introduction available in both HTML and PostScript formats.
A statistical analysis package called
ViSta that runs on
top of Xlisp-Stat and has some very nice capabilities is
also available. It' also worth occasionally checking the
Penn State pages on
Projects Based on XlispStat
as well as the Univ. of South
Teaching Statistics with Xlisp-Stat
project. There is also a site that specializes in keeping track of
- An extensible version of Xlisp which makes it easier to add
new C functions to Slisp. Slisp is also the basis for a 3-D
graphics package called skandha4 which is available in the same
directory. The skandha4 distribution contains the separately available
Slisp distribution. A 300+ page manual in Texinfo format is included
with the distribution. An online version of the
- A package that provides a point-and-click, dialog-laden interface
to Xlisp-Stat. The interface is extensible and includes features to
support various linked views. The source code, written in Xlisp,
is available as is documentation in PostScript format and various
examples and data sets.
- A utility to view several types of images under X11,
load images onto the root window, or dump compressed images into
one of several image formats. It currently reads many common and
some uncommon formats and can also create images in several
formats, including JPEG and TIFF.
The source code, written in C, is available and should install
on most generic UNIX/X11 platforms with the use of the Imake file
in the distribution.
The documentation is contained in a man page.
See also xv,
- A GNU program that allows monitoring of an almost
infinite number of logfiles and all other devices that can be read via
the cat command, e.g. the /proc files.
Xlogmaster has both TAIl and CAT modes, with the former performing
a similar duty to the tail program with more aesthetically
The latter concatenates a file or device at user-defined intervals, allowing
the user to keep track of any number of /proc devices.
The information retrieved by either mode can be processed in various
ways including displaying it in a text window.
Background monitoring is also supported, i.e. filters can be defined
that trigger certain actions based on substring matches.
A source code distribution is available.
Compilation and use require the GTK toolkit.
- A GUI program for data acquisition that uses
- A mail user agent (MUA)
for UNIX systems.
- A make utility that, while not compatible with
other makes, provides extended functionality over most standard
The features of XMake include:
A source code distribution is available. It is written in C and
portable to most UNIX platforms.
- specifying one-to-many and many-to-one
- applying a single command list to many one-to-one dependencies;
- embedding shell commands in variable and other definitions;
- generating wildcard template conversions on the fly, e.g. listing
source files and generating the object files and all dependencies from
the source file list;
- running the C preprocessor;
- maintaining special dependency variables that can be used in
- allowing variables to be .set inside a command sequence
where the .set directive is executed when the command sequence
is executed; and
- understanding delayed-expansion variable specifications wherein
the variable is fully resolved when used in a dependency or executed
as part of a command list.
- An interactive map displaying system for Linux platforms.
It lets you display digitized maps which, if they are in a
rectangular coordinate system, can be calibrated for navigation.
You can also measure distances and directions via a virtual
rubber band on the screen.
It can be connected to a GPS to plot your position on the
screen (via a gpsd daemon available separately).
Position changes can be logged to the disk and later replayed,
and you can also draw on the maps.
A binary version of Xmap is available. It requires
Motif 2.0 although both statically
and dynamically linked versions are available.
- This was renamed
Geotouch in Jan. 2000.
- A simple database manager and user interface builder which can
keep phone and address lists, store phone call logs, keep web
page databases, keep to-do lists, manage other databases
after a bit of GUI-driven customization, and custom export
to programmable data formats (with HTML export built in).
Xmbase-grok is used for displaying and editing strings arranged
in grids composed of rows and columns. The presentation format
of the data is programmable using a user interface builder
which allows the fields to be arranged graphically.
The package also contains a simple query language which allows
sophisticated queries and data retrieval.
It was designed for small applications typical for desktop
purposes, and may not be suitable for general purpose or
very large applications.
The source code for xmbase-grok is available and can be compiled
on any platform that has Motif.
A binary version is available which is statically linked to
the Motif library.
- A Motif-based BDF font editor whose
- simultaneously loading and opening multiple fonts;
- cutting and pasting glyphs between fonts;
- simultaneously using multiple glyph bitmap editors and cutting
and pasting between them;
- exporting XBM files from bitmap editors;
- automatic correction of certain metrics when a font is loaded;
- generation of XLFD font names for fonts without them;
- updating an XLFD font name from its properties;
- updating font properties from an XLFD font name;
- font property and comment editors;
- support for unencoded glyphs;
- built-in online help;
- importation of PK/GF, HBF, Linux
console (PSF, CP and FNT), Sun
console (vfont), X server, Windows FON/FNT and TrueType fonts;
- exportation of PSF and HEX fonts.
- A CD player with both graphical and command-line
The features as of version 2.4 (2/99) include:
Source and binary distributions are available, with one of the latter
being for Linux Intel platforms.
Compilation requires the Motif toolkit, although
statically-linked binaries are available.
- wwwWarp, a utility for controlling a Web browser from within
xmcd to visit sites related to the music currently playing;
- a dual-mode GUI main window with full-featured and reduced-footprint
- all the standard functions for playing, loading, ejecting, etc. CDs;
- multi-disc changer support;
- a direct access keypad for disc and tracking changes;
- selectable volume taper characteristics;
- a balance control;
- shuffle play, sample, and repeat functions;
- track programming to play tracks in custom order;
- a CD database function for storing and extracting information;
- remote CD database functionality via CDDB; and
- device-specific configuration files for most CD-ROM and CD-R drivers.
- A program for performing
simulations that was designed
mainly for simulating metals and ceramics.
XMD allows the generation of specific lattice structures on which
you can perform both static (energies or forces)
and dynamic (molecular dynamics) calculations.
An input file containing a description of an initial atomic system,
the simulation to be performed, and the desired output is used to
perform each simulation.
The features available for molecular dynamics simultions with XMD include:
- constant temperature using a velocity rescaling algorithm;
- constant pressure using one of two algorithms;
- an efficient system relaxation algorithm for finding local minima;
- constraining selected atoms to remain fixed in space or to remain
in a line or plane;
- application of a unique external force to individual atoms;
- tethering of selected atoms to their initial positions with
springs with various constants;
- application of velocity damping coefficients to selected atoms; and
- use of pair potential, Embedded Atom Method (EAM) potentials,
Tersoff's Silicon-Carbide potential, or the Stillinger-Weber Si
A source code distribution of XMD is available as is a user's manual
in HTML format.
The program is written in C and can be compiled using
to take advantage of machines with multiple CPUs.
- This software allows users to visually explore multivariate
data using a variety of methods. This is accomplished via several
data projection techniques as well as by the use of a concept
called an N-dimensional brush.
The data projection techniques in XmdvTool include:
- scatterplots, wherein n-dimensional clouds of points are
graphed and viewed from various perspectives;
- glyphs, any of a large number of techniques which map data
values to various geometric and color attributes of graphical
primitives or symbols;
- parallel coordinates, wherein each dimension corresponds to an
axis with the N axes organized as uniformly-spaced vertical lines and
with data elements manifesting themselves as a connected set of points;
- dimensional stacking, which involves projecting high dimensional
data by embedding dimensions within other dimensions; and
- brushing, a method for recovering the spatial relationships of data
when a given number of dimensions are projected onto a smaller number by
highlighting data points that fall into a user-defined subspace.
The source code of this package
is available and it appears to be installable on generic UNIX
boxes running X-Windows. It requires that both
the Athena widget set (Xaw)
and the WCL be first
installed. Documentation is available in the form of
a user's manual in PostScript format.
- See XMW.
- A Motif widget which provides the capability
of displaying any group of widgets as a graph, with each widget
representing a node.
The graph can be disconnected and contain cycles. The arcs
used to connect the nodes are instances of an
XmArc widget which was developed to work with the
The XmGraph widget has the ability to arrange all nodes either
horizontally or vertically according to an internal layout
algorithm, and it supports an edit mode in which arcs and
nodes may be interactively repositioned as well as created.
It also has a read-only mode in which all events are passed
directly to the children of the Graph widget.
A source code distribution of XmGraph is available.
It is written in C and can be compiled and used on a variety
of UNIX flavors.
The Motif library is required to
Both widgets are described in man pages.
- An interactive Motif widget set capable of displaying
HTML 3.2 text.
It consists of the XmHTML widget for displaying the text and
the XmBalloon widget for showing one-line strings in small
The features of the former include:
- built-in image support for XBM, XPM, GIF87a, GIF89a, JPEG and PNG;
- decoding of GIF images using a patent-free scheme;
- built-in support for animated GIF89a images;
- image support covering all X11 visual types and display depths;
- delayed and progressive image loading;
- a built-in scrolling interface;
- anchors which can be displayed as pushbuttons or highlighted;
- support for the full HTML 3.2 standard and 4.0 FRAMESET tags;
- an extensive set of callback resources;
- full text justification;
- smart and user-definable font mapping;
- four different dithering methods; and
- HTML table support.
A source code distribution of XmHTML is available. It is a Motif
widget and can be used with that toolkit, but fortunately it is
also compatible with the LessTif clone.
Documentation includes a programmer's and reference guide and
extensive man pages.
- The XML Metadata Interchange format specifies an
open information interchange model intended to give developers using
object technology the ability to exchange programming data in a
standardized way to ensure consistency and compatibility for applications
created in collaborative environments.
The chief purpose of XMI is for enabling the easy interchange of metadata
between modeling tools and between tools and metadata repositories
in distributed, heterogeneous environments.
XMI represents the integration of the
XML, UML and
MOF standards to combine the best of OMG and
W3C metadata and modeling technologies.
- The eXtensible Markup Language is designed to be
a bridge between HTML and
SGML on the Web.
XML is an application profile of SGML, i.e. a metalanguage which
allows you to define your own customized markup language.
It defines a simple dialect of SGML, the goal of which is to enable
generic SGML to be served, received, and processed on the Web in
a manner similar to HTML.
An XML standard is being proposed due to a growing consensus that
HTML is reaching the limit of its usefulness that further extensions
just cannot cure.
Related entries included proposed applications and initiatives include:
- AIML, the Astronomical Image Markup Language
is a framework for command and controlling astronomical instruments;
- AML, the Astronomical Markup Language, a
standard exchange format for metadata in astronomy;
- BSML, the Bioinformatic Sequence Markup
Language for graphic genomic displays;
- CDIF, for interchanging data among CASE
- CML, the Chemical Markup Language extends SGML
for the management of chemical information;
- DOM, the Document Object Model is an interface
allowing programs and scripts to dynamically access and update the
content, structure and style of documents;
- DRP, the Distribuion and Replication Protocol
is for improving the efficiency and reliability of data distribution
- ICE, the Information and Content Exchange protocol
is for use by content syndicators and their subscribers;
- IML, the Instrument Markup Language is a framework
that applies to any instrument that can be controlled by a computer;
- MathML, a low-level specification for
describing mathematics for machine communication;
- MCF, the Meta Content Framework provides a data
model for describing information organization structures for collections
of networked information;
- OMF, the Weather Observation Markup Format is for
encoding weather observation reports;
- OTP, the Open Trading Protocol provides an
interoperable framework for Internet commerce;
- PGML, the Precision Graphics Markup Language
is a scalable graphics standard;
- RDF, the Resource Description Framework provides
an infrastructure to support metadata across web-based activities;
- SDML, the Signed Document Markup Language is
for allowing signatures to become a standard part of a document;
- SGF, the Structured Graph Format is for describing
the structure of Web sites;
- SMIL, the Synchronized Multimedia Integration
Language allows the integration of multimedia objects into a synchronized
- Topic Maps, a standard allowing the creation
and maintenance of consistent electronic indices, glossaries, thesauri
and tables of contents for multiple heterogeneous documents;
- VML, the Vector Markup Language is for encoding
vector information and how it should be displayed;
- WDDX, the Web Distributed Data eXchange is
a method for exchanging data between differing Web development platforms;
- WIDL, the Web Interface Definition Language is
a metadata syntax for defining APIs to Web data and services;
- WML, the Wireless Markup Language is for specifying
content and user interfaces for cell phones and pagers;
- XBEL, the XML Bookmark Exchange Language is
a format for exchanging bookmarks;
- XLF, the eXtensible Log Format is intended to
make log information smarter and easier to use;
- XMI, the XML Metadata Interchange format specifies
an open information exchange model for exchanging data in a standardized
way using object technology;
- XML-RPC, a specification and set of
implementations for allowing software running n disparate systems and
environments to make procedure calls over the Internet; and
- XSL, the eXtensible Style Language is a stylesheet
language designed for the Web.
- A Java-based XML parser.
It was designed to be small, use few class files, maximally portable,
to use little memory, to run fast, to produce correct output for well-formed
and valid documents, and to provide full internationalization.
A source code distribution is freely available for both commercial
and non-commercial uses.
- A Java package for the processing and layout
of XML documents based on
It can be used as a server-side preparser for serving XML
documents on the Web.
- An XML 1.0 parser written in C.
- A Open Source, cross-platform
XML toolkit that
includes its own parser.
The features include:
- a fast and efficient parsing algorithm;
- written in standard C++ for portability; and
- extensive documentation including a design dcoument and an
- An XML browser written in
It can be used either as an applet or a standalone application.
- A non-validating XML processor implemented
in the Java language which attempts to
achieve reasonable trade-offs among compactness, completeness,
- libxml (Perl)
- A collection of modules, utilities, examples and documentation for
use with the major Perl
The modules in this package include:
- XML::Parser::PerlSAX, a Perl SAX parser that uses
- XML::Handler::Sample, a Perl SAX handler that prints out the
event names as they are parsed by a SAX parser;
- XML::ESISParser, a validating Perl SAX parser that uses
- Data::Grove, Data::Grove::Tied and
Data::Grove::Visitor, provide a base class for deeply nested or
directed graph structures; and
- XML::SAX2Perl and XML::Perl2SAX, for translating
parse events between the Java/CORBA style SAX methods and
Perl style SAX methods.
- LT XML
- An integrated set of XML tools and a developer's
toolkit including a C based API.
The toolkit includes standalone tools for a wide range of processing
tasks involving well-formed XML documents as well as the library
from which the tools are constructed. The library can be used to
construct further tools and applications.
The programs in the LT XML toolkit include:
A source code distribution of LT XML can be freely obtained upon the
completion of a research license agreement.
- sggrep, a program for querying XML files;
- sgmltrans, translates XML files into other formats;
- sgrpg, systematically transforms input documents to changed
- knit, processes compound documents using hyperlinks;
- unknit, created hyperlinked files from XML files;
- sgmltoken, a tokenizer;
- sgmlseg, a toy segmenter;
- sgmlsb, a sentence boundary finder;
- pesis, a simple version of nsglms;
- simple and simpleq, example programs;
- textonly, for outputting all the text from an XML file;
- nslshowddb, a utility program for printing .ddb files;
- sgcount, for counting the amount of markup in a file;
- sgsort, for sorting sub-trees of SGML documents; and
- xmlnorm, for trivial normalization of XML files.
- A validating XML parser written in
- Simple API to XML is
a standard interface for event-based XML
parsing. Implementations are available in both
- A Java class library for processing
XML documents that provides a set of services
particularly useful for applications performing XML-to-XML or
It is designed to help write applications that process a specific
document type, and is less useful for writing general purpose
applications such as editors.
SAXON works by serially scanning a document and calling user-defined
element handlers to process each element.
- A parser for XML written in
- An Emacs major mode for editing
SGML and XML DTDs.
The features include:
- a function for creating Emacs TAGS file for easily looking up
any element, parameter entity, or notation definition;
- a function for searching files that share a file history;
- font lock highlighting of declarations;
- XML-specific behavior triggered by automatic detection of
the XML Declaration;
- functions for writing and editing element, attribute, internal
parameter entity, and external parameter entity declarations and
- storage of elements and parameter entity names referenced in
declarations in a minibuffer history.
- A Java program for creating TeX
typeset documents from XML markup.
The translation procedures starts by writing an XSL transform that
transforms an existing XML document with a given document type into
a new XML document conforming to the TeXML document type.
This is then translated into TeX and then processed like all other
TeX documents to produce printable output.
The package consists of three parts:
A source code distribution of TeXML is available.
It also requires JDK 1.1, an
XSL implementation, and an
XML parser (e.g. xml4j).
- TeXML.dtd, an XML document type definition;
- TeXML.java, a Java program which takes a DOM conforming to
TeXML.dtd and outputs TeX source code; and
- TeXMLatte.java, a Java program that translates an XML
document conforming to TeXML.dtd and outputs TeX source.
- Visual XML
- A visual tool for creating DTD and
Versions are available under an
Open Source license.
They will work with JDK 1.1.8 and greater
and Swing 1.1.1.
- The World Wide Web Wrapper Factory
A toolkit for the generation of wrappers for Web sources.
This is a Java toolkit that makes it easy
to transform HTML pages into XML documents.
W4F consists of a retrieval language to identify Web sources,
a declarative extraction language (HTML Extraction
Language) to expression robust extraction rules, and
a mapping interface to export the extracted information into
some user-defined data structures.
The kit also offers some WYSIWYG support via wizards that facilitate
the automatic generation of wrappers generated as
- A Java package that allows the processing of
architectural forms with any Java-based,
SAX-conformant XML parser.
The core of the package is a SAX driver that sits between a regular
SAX parser and the client's document handler, translating the SAX
events according to the specified base architecture.
This allows an XML document to masquerade
as many different documents by associating the document with one
or more base architectures, e.g. embedding RDF or
MathML in an XML document without actually
using the element type names for those languages.
- A validating XML parser written in pure
Java. The package contains classes and methods
for parsing, generating, manipulating and validating XML documents.
This conforms most closely to the XML 1.0 recommendation than
any other currently (5/98) available processor.
- A reference XML 1.0 validating parser.
This is especially useful for legacy SGML
documents in the process of being converted (along with their
DTDs) into XML.
This knows the difference between SGML and XML and can often
identify mistakes stemming from SGML/XML incompatibilities.
- XML Toolkit
- A toolkit implementing an open architecture for developing
XML-based Web applications.
The features include:
A source code distribution is available.
- implementation in Python;
- a client/server XML Processor based on the Paos
client/server database engine; and
- an implementation of WIDL.
- A specification and set of implementations for allowing software running
on disparate operating systems and in disparate environments to make
procedure calls over the Internet.
XML-RPC is remote procedure calling (RPC)
using HTTP as the transport and
XML as the encoding.
It is designed to be as simple as possible while still allowing
complex data structures to be transmitted, processed and returned.
- The X MultiMedia System project is
for the development of
a cross-platform multimedia player that supports
MP3, Wave, CD, MOD, MIDI and other digital audio and video formats.
It also provides MP3 streaming playback support over the Internet
and visual graphics synchronized to sound output.
The features include:
- playing functions including seeking in files, volume/balance,
shuffle and repeat play, an equalizer, and a playlist editor;
- waveform visualization tools including a spectrum analyzer and
- a GUI interface dock application for various window managers;
- plugins for visualization, effects, input and output;
- fast jump in playlist;
- scroll wheel support; and
- proxy authentication support.
- An XMMS plugin for playing Advanced Audio Coding
(AAC) files coded with FAAC.
- Volume Normalizer
- An XMMS plugin for ensuring that all songs
have about the same volume level.
- An XMMS plugin for playing
- A file transfer protocol is used for the error
free transmission of text and binary files over asynchronous communications
lines, e.g. phone lines.
This protocol was introduced by Ward Christensen in 1977 via his
MODEM.ASM program with the name originating with a related program
called XMODEM.ASM which adapted MODEM.ASM for Remote CP/M systems.
This has also been variously called MODEM, MODEM2 and MODEM7.
Limitations in XMODEM were addressed by various enhanced XMODEM
protocols and eventually with the YMODEM protocol.
The enhanced version of XMODEM included:
- XMODEM/CRC, which replaced the XMODEM one byte checksum with a
two byte cyclic redundancy check (CRC) to improve error detection; and
- XMODEM-k, a version of XMODEM/CRC with optional 1024 byte blocks
to reduce the overhead from transmission delays.
- A tool that supports the movement of an application's X11 interface
from one X server to another. It is implemented as a pseudoserver,
i.e. a program interposed between client and server that looks like
a server to the client and like a client to the server. The xmove
pseudoserver or proxy operates by spying on all X protocol messages
and retaining any information needed to move a client from one server
A source code distribution of xmove is available.
It is documented in a thesis available in PostScript format.
- A movie player for MPEG-2, DVD and Quicktime movies with stereo
sound (although it won't play Quicktime movies downloaded from the
Internet that are compressed with Sorenson Vision).
This is used to play long, unencrypted DVD files and
high-resolution Quicktime movies captured or composited yourself.
It is the only player supporting synchronized audio and video for
DVD, and the only convenient player for movies over 50 minutes.
It also supports aspect ratios and stereo sound, highly useful
features for a VCR replacement.
This is based on LibMPEG2, and
works for movies created with
MPEG-2 Movie as well as for VOB
files obtained from the Internet.
The supported MPEG-2 formats are MP2 and MP3 audio,
AC3 audio, MPEG-2 video, program and elemental streams.
- The extended module player is an
sound module player.
On PC-based machines with GUS or AWE cards
it can take advantage of the OSS sequencer
to play modules with almost no system load.
It plays (using software mixing) at sampling rates up to 48 KHz
in mono or stereo, 8 or 16 bits, signed or unsigned, and little
or big endian samples with 32 bit linear interpolation.
This supports 46 MOD file formats.
- A user interface framework for the C++ language designed to be
a simple and intuitive programming interface to access the functionality
of commonly used GUI toolkit objects.
Xm++ was originally built upon X11 and the X toolkit, but
it has evolved into an experimental system for developing
multi-platform and client/server GUIs.
It currently (4/97) supports Motif,
Xaw (to a limited extent), and
The top level objects in Xm++ are
Windows, SystemDialogs, and ToolBoxes, which use
the automatic layout feature of various composite widgets in
Motif and Xaw, and UserDialogs, which can be individually
laid out with a user interface builder.
These top level objects control various child objects such
as staticText, staticImage, pushButton,
checkBox, radioButton, edit, listBox,
comboBox, groupBox, paneArea, drawing, and
The staticImage and all of the button classes can display
XBM or GIF pictures as an alternative to a label text,
and event handling is done by a simple but easy to use mechanism
which redirects Xt callbacks to member functions of Xm++ objects.
The Xm++ source code is available and can be compiled with
g++ and other C++ compilers.
Configurations are supplied for Sun SunOS, HP-UX, SGI IRIX,
IBM AIX, and Linux intel platforms.
The system is documented in a user's guide available in
- XMU Library
- The eXtended Mathematics and Utilities library is
a C++ library for geometric algebra, tensors,
matrices and utilities.
The library is split into three parts:
Source code distributions of this are available for libc5 and libc6,
and documentation includes user's and reference manuals in PostScript
and PDF format.
- XUT, an eXtended UTilities library including classes for
dynamic memory allocation and character string manipulation;
- XGA, an eXtended Geometric Algebra library which implements
the operations of geometric algebra including addition, subtraction,
division, geometric product, inner and outer product, commutator and
anti-commutator product, negation, reversion and inversion, dual, join,
meet, projection and magnitude squared;
- XMA, a library containing matrix, tensor and random number
- X Multimedia Project
- A project to create a modular, highly extendable multimedia system for
creating, playing and converting multimedia files and streams on
Linux. It also aims to create a Media Player for Linux.
The project is divided into three parts:
- a multimedia library (libxmm) providing the interface
between applications and input/output plugins;
- plugins, i.e. dynamic libraries that support input and output formats
as well as graphics and sound devices; and
- a media player, i.e. a skinned user interface to the libraries.
The features include:
- audio support for WAVE (PCM and GSM 6.10), MPEG (1,2 and 2.5 Layer 1,
2 and 3), and all module formats supported by MikMod;
- video support for MPEG 1, MPEG2 and ac3 audio, and AVI;
- sound output for ALSA and
- graphical output for X11 and
- XMegaWave is a GUI image processing environment wherein
images can be viewed and saved in several formats as well as manipulated
with a large number of classical image processing procedures.
Pictures can also be created using various geometric primitives.
XMW is also an extensible library wherein all of the functionality of
the GUI is available and additional functionality can be added via
a well-defined procedure.
The main GUI window of XMW contains menus for file access,
editing, morphological filters, edge detection/segmentation, and
Versions of this are available for several platforms including
A user's manual is available in the usual formats.
- The X Protocol MultipleXor is
a standalone utility for sharing an X Window
session on multiple X displays. It lets users see and interact with
the same applications at the same time from different locations.
XMX takes advantage of the client/server nature of X11 by acting as
an intermediary between clients and servers, and as such neither
needs to be modified for it to work.
The features and functionality include:
The source code is available as are binaries for several
platforms including Linux Intel.
- creation of a virtual X environment that is strictly WYSIWIS (What
You See Is What I See) wherein all participants see exactly the same thing;
- a shared, nested X server in a window under the control of the
local user and which may be resized or iconified independently;
- no imposition of policy on run-time application sharing, i.e. provision
of application sharing services to multiplexor clients that control
XMX via a separate wire protocol (XMCP);
- X server control over shared applications via three modes: (1) all
server inputs are forwarded to interested applications; (2) all inputs
are forwarded to the XMC client; and (3) all such inputs are ignored;
- defintion of any number of remote telepointers independent of
local X server pointers/cursors; and
- efficient performance via short-circuiting much protocol activity,
minimizing internal copying and moving all data asynchronously.
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